Stress-Optical Coefficient of Poly(ethylene oxide) and Poly(propylene oxide) Networks. Measurements

Measurements of stress-optic coefficient in polymer optical fibers.

We have systematically measured the differential stress-optic coefficient, DeltaC, in a number of poly(methyl methacrylate) (PMMA) fibers drawn with different stress, ranging from 2 up to 27 MPa. DeltaC was determined in transverse illumination by measuring the dependence of birefringence on additional axial stress applied to the fiber. Our results show that DeltaC in PMMA fibers has a negative...

Creep and Stress Relaxation Behavior of Polypropylene, Metallocene-Prepared Polyethylene and their Blends

Biodegradation of polyethylene and polypropylene

Polyethylene and polypropylene are the two polyolefins with wide ranging applications. They are recalcitrant and hence remain inert to degradation and deterioration leading to their accumulation in the environment, and, therefore creating serious environmental problems. In this review, biodegradation of these two polymers under in vitro conditions is reported. An attempt has been made to cover ...

Enhancement in Mechanical and Electrical Properties of Polypropylene Using Graphene Oxide Grafted with End-Functionalized Polypropylene

Terminally hydroxylated polypropylene (PP) synthesized by a chain transfer method was grafted to graphene oxide (GO) at the chain end. Thus obtained PP-modified GO (PP-GO) was melt mixed with PP without the use of a compatibilizer to prepare PP/GO nanocomposites. Mechanical and electrical properties of the resultant nanocomposites and reference samples that contained graphite nanoplatelets, par...

Polyethylene glycol and a novel developed polyethylene glycol-nitric oxide normalize arteriolar response and oxidative stress in ischemia-reperfusion.

Polyethylene glycol (PEG) has been shown to repair cell membranes and, thus, inhibit free radical production in in vitro and in vivo models. We hypothesized that PEG and newly developed organic nitrate forms of PEG (PEG-NO) could repair endothelial dysfunction in ischemia-reperfusion (I/R) injury in the hamster cheek pouch visualized by intravital fluorescent microscopy. After treatments, we ev...